ipwclas: Estimates the avarage treatment effect (ATE) using the...
In mvaldora/SPPS:

Estimates the avarage treatment effect (ATE) using the classical model (epsilon=delta=0)

1 2	ipwclas(x, a, y, phi = expit, dphi = dexpit, phiinv = expitinv, estim.method = "ML", type = 1)

`x`	A matrix of covariates of dimension n x p
`a`	A vector a of 0s and 1s of dimension n
`y`	A vector of responses or outcomes
`phi`	A function that maps the real line onto the interval (0,1)
`dphi`	The derivative of `phi`
`phiinv`	The inverse of `phi`
`estim.method`	The estimation method to be used for estimating the parameters "ML" (default) or "LS"
`type`	The type of IPW estimator to be used: type 1 , type 2 and type 3 combine SPPS with, respectively, IPW1, IPW2 and IPW3 in Lunceford and Davidian(2004)
`maxit`	The maximum number of iterations to be performed.